Rotary pump or motor



Dec. 27, 1938. H. A. CENTERVALL Y 2,141,170

ROTARY PUMP o R MTOR original'riied April 13, '1954 3 Sheets-Sheet 1 los INVEN TOR BY. l v

fz.; ATTORNEYS Dec. 27, 1938.4

H.v A'. cENTERvALL. ROTARY PUMP (0R MOTOR Original Filed April" 1s, i954 3 Sheets-Sheet 2 'Il vll' lil INVENTOR.

v 133 ATTORNEYS Dec. ,27, 1938. f A H. A. cENTERvALL A 2,141,170

ROTARY PUMP OR MOTOR original Filed April 15, 1934 5 sheets-sheet s 93 mii ,':Jl L i Y 95 9.4 E El 8l 82 a0 Fig. E1

INVENTOR.

BY 'j Ml M4/w 755' 'ATTORNEYS Patented Dec. 27, 1938 UNITED STATES ROTARY PUMP on. Moron Hugo A. Centervall, Brooklyn, N. Y., assignor to vManly Corporation, New York, N. Y., a corporation of Delaware Application April 1?., 1934, Serial No. 720,418 Renewed June 19, 1937 33 claims. (c1. 10s-120) This invention relates to improvements in rotary type fluid pumps or motors, and the invention is concerned more particularly with pumps or motors of this sort in which the rotor is provided D with a plurality of vanes which are suitably mounted and arranged to move outwardly and inwardly thereof during the operation of the device, for example, in a general radial direction.

Such pumps or motors may be used with either lo an elastic fluid such as air or steam, or with liq- Se pressures, and rotary pumps and motors of this general type have proved to be industrially and commercially successful. Such pumps and'motors, however, have a serious limitation in that it is impossible to control, or vary, their capacity, g or output, except by varying the speed of rotation. The principal object of the present invention is to provide a pump or motor of this kind in which the capacity, or. output, of the pump or motor at .constant speed, o1' in other words, its gn capacity per revolution, can be readily controlled or varied whilethe pump is in operation, and yet `,retain the simplicity of construction which is nec- \essary for long and dependable service when operated continuously, or intermittently, at pressures employed in modern commercial hydraulic apparatus.

rAn object of the `invention also is to provide such auid pump or motor in which the capacity per revolution can be Yvaried in infinitely small pump or motor to the maximum, and which operates with remarkable quietness and freedom from vibration and wear at all capacities and pressures within the intended range of operation. 5 Another object of the invention is to provide a uid pump or motor of this kind which is compact, comprises a comparatively small number of parts, and is constructed so that it is relatively inexpensive to manufacture. Other and more speciiic objects will appear whichfollows. x

The invention will be understood from a conf sideration of the accompanying drawings which illustrate, by way of example, an embodiment of 55 the invention in a pump of variable capacity in increments from the minimum capacity of thefrorn the description the rotor in a substantially radial direction.

In the accompanying drawings:

Fig. 1 is a sectional View transverse the axis of rotation taken along theline l-I of Fig. 2 looking in` the direction of the arrows.

Fig. 2 is a longitudinal view, partly in section, taken alongthe line 2--2 of Fig. l.

Fig. 3 is an enlarged view, the right hand half being in section taken'on the vertical center line ofFig. 2, and the left hand half being in section taken on line 3--3 of Fig. 2 showing' the valve ports and oil passageways' in the rear casing member. v

Fig. 4-is an enlarged side elevation, drawn on substantially the same scale as that used in Fig. 3, of one of the members which for convenience is termed .the movable abutment.

Fig. 5 is a top plan view of the movable abutment drawn on a smaller scale than that of Fig. 4.

Fig. 6 shows in perspective, other details of construction oi' the movable abutment and is drawn on substantially the same scale as that of Fig. 5.

Fig. 'l shows in detail an inner elevation of another of'the members, which for convenience is termed-the end plate. n

Fig. 8 is a side elevation of another of the members which for convenienceis termed the central distance piece.

Fig. 9 is a plan view' of the central distance piece.

Referring no w to these drawings, as shown inA Fig. 2 the enclosing casingincludes aforward member 20 and a re'ar member 2| provided with cooperating flanges 22 and 23 respectively and securely held together as by screws 24, appropriate packing 25 being used to prevent leakage. The pump is supported by a base 26 which in' this instance is formed integrally with the casing member 20. The casing member 20 is also formed with a centra] cylindrical bore 21 whose rear end is enlarged to form the pump cavity 28 having a face 29 at right angles to the bore 2l. The rear casing member 2| is likewise formed with a bore 30, in line with the bore 21 of the member 2|) and in the present embodiment of the same diameter as said bore 2l, and is .provided with a face 3l which is parallel to the f ace 29 of the member 20 and closes the pump cavity 28. v

The enclosing casing is further provided with a pair of openings 35 of substantially rectangular cross section, each having three sides formed in the casing member 2U and a fourth side formed by the face of the casing member 2 I. These openu I'. l which the va'nes move outwaryhwiriwardly of f' 'rically opposed pair of the screws ings are positioned on opposite sides of and in line with the axis of pump cavity 28, as shown in Figs. 1 and 3, and their outer ends are closed as by cover plates 36 suitably held in place, as by screws 31.

'I'he driving shaft 40 is rotatably supported by the bearing members 4| and 42 respectively and is held against endwise movement by the shoulder 43y which bears against the inner race of the bearing 4| and by the shoulder 44 which bears` against the inner race of the bearing 42. 'The bearing 4| is positioned in the enlarged end portion of the bore 21 and is held against endwise movement by the shoulder formed bythe inner end of said enlarged portion, and by the cover member 32 which closes the outer end of said bore 21 and which is suitably held in place as by screws 33. 'I'he bearing 42 is similarly positioned in the reduced end portion of the bore 3|)` and is held against endwise movement by the shoulder 44 on "-he driving .shaft 40 and by the cover member 34 which closes the outer end of the bore 30 and which is suitably held in place, as by screws 38. Formed on each side of the rotor 50 is a sleevelike hub 5| extending into the bores 21 and 3|)y respectively, as shown in Fig. 2, and supported therein in a manner to be later described. `'I'he arrangement is such that the rotor 58 is supported by its hubs 5| but is driven by the driving shaft 48 which passes loosely through hollow hubs 6| and is keyed thereto by means of sliding keys 45 which allow the rotor to move lengthwise of the driving shaft.

The rotor 50 is provided with a plurality o'f conventional l slots 52 in each of which is slidably fitted the usual vane 55 of substantially the same Width as said rotor 50 and preferably of a length slightly less than that of the slots 52.

Located within the pump cavity 28 is a pair of members 60 (Figs. 2 and 7), hereinafter termed end plates, one of which is positioned on each side of the rotor'50 (see Fig. 2). Each end plate 6l) comprises a disc-like portion 6| which in the present embodiment is of a diameter slightly less than the distance between a diamet- 24, as indicated by the dotted lines in Fig. 1 and as shown in Fig. 2. Each end plate 60 has a pair of short arms or extensions`62 (see Fig. 7) which in the present embodiment are of a Width substantially equal to the vertical dimension of the rectangular openings 35, and one of said arms 6211s provided with a suitable drill hole 63 to receive a dowel pin, not shown, which securely and accurately locates the member.

Each end plate 6U also is provided with a hub 64 (see Fig. 2) 'at right angles to the disc-like portion 6| and fitting snugly Within the bores 21 or 30 respectively, as shown in Fig. 2. AnA appropriate bore to receive the rotor supporting hubs 5| is formed in and extends through each end plate 6|) and its hub 64. 'Ihe disc-like portion 6| of end plates 68 is made of such thickness as to ll the space between the sides oi the rotor 50 and the faces 29 and 3| respectively of the pump cavity 28, Aand the hubs 64 are similarly made of such thickness as to ll the space be- 1 tween the hubs 5| of the rotor 50 and the inner circumferential surfaces of the bores 21 and 3|) respectively, as shown in Fig. 2. The arrangement is such as to'permit the rotor 50 to rotate freely while forming substantially uid tight running joints with the cooperating surfaces of the end plates 60.

Each end plate 60 is formed with two pairs of diametrically oppositely positioned arcuate ports 65 and 66 respectively whose inner sides are substantially in line with the periphery of the rotor 50 (Figs. 3 vand 7). These ports 65 and 66 form part of the fluid circuit, to be later described, and in the present instance the ports 65 are the inlet or suction ports and the ports 66 are the discharge or high pressure ports.

Located Within the pump cavity 28 and positioned 'between the opposing faces of the end.

plates 60 is a pair of members 10 (Figs. 8 and 9) hereinafter termed central distance pieces. Each central distance piece 10 comprises a nearly semi-circular segment of a ring whose outer surface is adapted to conform to the bore of the pump cavity 28 and whose inner surface is greater in radius than rotor 50. 'I'he ends 1| of the central distance pieces 10 are so formed as to be horizontal, in the present embodiment, when the parts are-in position. Each central distance piece 10 is located by a dowel pin 12 tted into an appropriate drill hole and is securely held in lplace as fby screws.13 projecting inwardly through the enclosing casing 20. The central distance pieces 10 are made of a thickness slightly greater than the thickness of the rotor 50, the arrangement being such that the end plates 68, while pressing against the sides of the central distance pieces 10 so as to prevent the leakage of fluid therebetween, are maintained in such position as to permit the rotor 50 to rotate freely while forming substantially fiuid tight running joints therewith as hereinbefore stated. Each central distance piece 10 is likewise provided with drill holes 14 through which pass the screws 24 as clearly shown in Figs. 1 and 2.

The device includes means for dividing the space surrounding the rotor into a plurality. of pumping sections, preferably two, each consistlng of a working or pumping chamber flanked by inlet and outlet areas. It also includes means comprising a track for the outer edges of the vanes for Varying the extent of and for controlling the inward and outward movement of the vanes 55 and which constitute important features of the present invention. In the present embodiment the mechanism for dividing the space surrounding the rotor into two pumping sections includes a pair of fixed abutments 15 here shown as formed integrally with and extending inwardly from the central distance pieces 1|] and-which in the present instance are positioned respectively above and below the rotor 50 and substantially in line with its Vertical center line. Each fixed abutment 15 includes an arcuate surface 16 (Fig. 8) adapted to appropriately cooperate with the periphery of the rotor 50, the arrangementbeing such that the vanes of rotor 50 form substantially fluid tight running joints with saidarcuate surfaces 16. The 110W of fluid past the fixed abutments is restricted not only by the vanes, but by the proximity of the peripheral surface of the rotor to the arcuate surfaces 16 even though the t between these surfaces may be comparatively loose.

y'Ihe working or pumping chambers,lor pumping spaces,v of the two pumpingI sections are formed by means of a p'air of members 80, hereinafter termed the movable abutments, vone of which is shown in Figs. 3,l 4, 5 andl 6.

These members 80 are arranged to be conjointly adjustable radially as W-ill be later explained, and the size of the pumping chambers and the volume of duid delivered by the pumpare determined by the distance of the inner ends of these members from the rotor, the pumping chambers being comprised by the spaces between the adjacent vanes l which are moving in contact with the inner ends of movable abutments 80. It will be understood that the width oflabutments 89 is equal to the distance between the` opposing faces of end plates 60 with which they form substantially fiuid tight `joints. The curved surfaces of the inner ends of these abutments form elements of the vane track, as wi-ll be described presently."

Each movable abutment 80 includes a horizontal member comprising a portion 8| of rectangular cross section, having a -width equal to the distance between the opposing faces of the arms 62 of the end plates 60, and having a height equal tothe distance between the opposing ends 1|v of the pair of central distance pieces 10. Each movable abutment 80 is thus supported by its rectangular portion 8| which in turn is-supported by the ends 1| `of the central distance pieces and the arrangement is such that the movable abutment 80 may be moved any desired amount horizontally with respect to the device while said portion 9|. forms a substantially fluid tight joint with the opposing faces ofthe arms 82 of the end plates 6|) and with the surfaces of the ends 1| of said central distance pieces 1|).

Outwardly. of the rectangular portion 8| is an enlarged portion 82 which acts as a stop, and is hereinafter so termed, limiting the maximum inward and outward movement of the movable abutments 80. Extendingoutwardly from the -stop 82 is a portion 83 which lprojects through the ends of the openings 35 ofthe enclosing casing and through appropriate openings inthe cover plates 36. Each outer portion 83 is fiattened at 84 (Figs. 1 and 3) and drilled at 85 to receive a pin 86 by which eachl movable abutment 80 is operatively connected with one end of a forked link 81 Whose purpose will be` explained later.

A Each movable abutment 80 carries vane trackway elements 92 which in the present embodiment are of somewhat parabolic shape and formed integrally with the horizontal member already deand forms a continuous tra'ck for guiding the outerI -ends of the vanes as they move, by the rotation of the rotor, between the fixed abutments and the pumping arcs 9|, and vice versa.

The pumping arc 9| may be of any desired curvature but is preferably made such as to be concentric with the periphery of the rotor 50.

when the moveable abutments 80 are in the position of adjustment at which thepump is intendedto receive its greatest use; in the present embodiment the pumping arc 9| is concentric with the periphery ofsaid rotor 50 when the movable abutments 80 are midway between their extreme inward vand outward positions of adjustment. By this arrangement, radial' movement of thel vanes while subjected to working pressure, that is, while moving` across the pumping space arc 9| is kept at a minimum, ,as will vbe later explained. The pumping arc. 9| is also preferably of a length in a circumferential direction equal to or slightly greater than the angular distance between the vanes 55.

`The track elements 92 extending from opposite sides of the pumping arc 9| comprise two nonrigid, flexible, or yielding arms orl branches projecting integrally from the sides of the movable abutments 80. 'I'hese arms, in the present in- Stance, are of a width slightly less than the disillustrated, the surfaces of the inner ends of these l arms adjacent each of these abutments are necessarily maintained even with the surfaces of pumping arcsSI. However, in order to obtain proper action and radial movement of the vanes 55 it is necessary also to provide the vane track with means which permit and cause the outer ends of said vanes 55 to pass smoothly and without interruption from the outer ends of arms or vtrack elements 92 onto the arcuate surfaces 16 of the xed abutments 15 and similarly from said arcuate surfaces 16 onto said arms 92. In the present embodiment this is accomplished by proportioning the parts so that the ends of the arms 92 'over-lap With the outer portions of the arcuate surfaces 16 of the fixed abutments 15, and by maintaining the surfaces of said overlapping portions of said arms 92 even with said arcuate surfaces 1.6so that said arms 92 have a tangential relation, at or near their ends, to said arcuate surfaces 15. The particular mechanism employed for this purpose in the present embodiment will now be described.

Projecting outwardly from the end of each arm 92 is a substantially rigid member 93 whose outer end is formed integrally with or rigidly attached to an arcuate flange 94; as here shown, the member 93 is positioned radially with respect to said flange 94 and the arcuate surfaces 16 of the fixed abutments 15. The flanges 94 are of greater width than the arms 92, and the outer edges of eachv of said flanges are adapted to be received in the adjacent pair of arcuate channels 91 formed in the opposing faces of the end plates 60; the channels'91 are of greater length than the flanges 94 and are likewise positioned concentrically with respect to the arcuate surfaces 16 of the xed abutments 15. The arrangement and fit of the parts is such that fthe anges 94 are free to slide in the channels 91 but are at all times held concentric with the arcuate surfaces 16 of the fixed abutments 15. l

The end of each arm 92 is provided with a slot 95 (Fig. 6) into which is received a tongue 11- (Figs. 8 and 9) extending circumferentially from and forming part of the arcuate surface 16 of the corresponding fixed abutment 15.- The arrangement is such'that the tongues 11 extend into the slots 95 and thus overlap the ends of the corresponding arms 92 in all' positions of adjustment of the movable abutments 89, and the anges 94 controlled lby 'the slots 91 maintain at all times substantially tangential or even relation between the surfaces ofjsaid arms and the arcuate surfaces 16 of the fixed abutments 15.

There may also be provided means for control-v ling the relative rates of inward and outward movement, i. e. the -radial acceleration and deby proper proportioning' of the flexible arms 92 of the movable abutments 80 and by exerting upon said arms 92 force in such amount and direction as to cause said arms to assume desired predetermined shape. The mechanism employed for exerting this force upon the arms 92 may be of any preferred type and may be separate from, combined with, or, as in the presen-t embodiment, integral with the mechanism employed for maintaining the end portions of said Aarms 92 in line and substantially concentric with the arcuate surfaces 16 of the fixed abutments, 15. The

flexible arms 92 may, therefore. be made of any desired interior coniiguration and of any desired thickness; in the present embodiment, however, the arms 92 are made of variable thickness, de-

creasing toward their ends. 'I'he interior sur faces of the arms 92 are preferably ground so as to have a configuration adapted to produce vane movement at the desiredacceleration and deceleration when no force is exerted upon the arms 92 by the mechanism provided for this purpose.

In the present embodiment the arrangement is such that no force is exerted upon the arms 92 when the movable abutments 80 are midway between their extreme inward and outward positions of adjustment and said arms 92 are ground to have the desiredcconflguration when saidfmovable abutments 80 are in this mid-position, as shown by the full lines of Fig. 4. As hereinbefore stated, at mid-position, the pumping arc 9| together with its corresponding pair of arms 92 form a substantially true parabolic configuration in the present embodiment. As vthe movable abutments 80-,are moved out of theidmid-positions the flanges 94 are at the same time moved in one direction or the other in their channels '91, which movement tends to change the angular relation between each `member 93 and its arm 92 and thus exerts force upon said arms 92. The flanges 9d.. the members 93 and the channels`91 therefore not'only serve to maintain the surfaces of arms 92 ev'en with the arcuate surfaces 16 of the fixed abutments 15 but also act to exert force upon said arms 92, i I' The arrangement, therefore, in the embodi ment illustrated in the accompanying drawings,

treme inward and outward positions of adjust--v By proper variation of proportions, of positional arrangements and, if desired, of force exerting mechanism the flexible arms 92 may be made to assume almost any desired configuration so that the inward and outward movement of the vanes 55 may be made to occur at practically any desired rate. The method of construction herein ,describedhas theadvantage, however, of reducing to a minimum the deflection away from norl mal position of said arms 92 asthemovable abutments are moved from one to the other of their extreme positions of adjustment.

- Mechanism is also provided for effecting and controlling the movement of the movable abutasvat |0| upon brackets |02 projecting from each side of the enclosing casing. The upperl ends of the arms |00` are likewise pivotally connected with a pair of l sleeve members |03 whose inner ends are internally threaded to receive the oppostely threaded ends of an adjusting rod which is rotatably positioned in a slot |01 formed in a bracket on the upper end of the enclosing casing. The adjusting rod |05 is held against endwise movement by a shoulder |06 formed on said rod |05 and by the inner end of a hand wheel |'08Vwhich are positioned on opposite ends of the slot |01 and which bear against the faces of the bracket. The hand wheel |00 is keyed to the adjusting rod 05 as by the set screw- |09.

Each movable abutment 80 is operatively connected with its corresponding lever |00 by its corresponding link 81 whose outer end is pivotally connected to said lever |00 intermediate its ends,j as by a pin 88. The arrangement is such that clockwise rotation, as viewed from the right of Fig. 1, of the hand wheel |08 simultaneously forces the upper end of each lever |00 an equal outward distance, which in turn produces. simultaneous and 'equal outward movement of each movable abutment 00. Similarly counterclockwise rotation ,of the handwheel |08 produces simultaneous and equal inward movement of each movable abutment 80. The stops 82 coming in'contact with the end cover plates 36 limit the maximum outward movement of the movable abutments 80 and likewise said stops 82 coming in contact with the outer edges `of the central distance pieces limit themaximum inward movement.

It will be understood that other mechanism for I moving the adjustable abutments 80 may be used. The mechanism disclosed moves the two abutments conjointly but this is not necessary. Vari ation in output can be effected by moving only one ofthe abutments or by unequalmovement of the two abutments.

The iiuid circuit comprisesa pair of annular channels ||0, one of which is formed in each of the casing members 20 and 2| respectively as shown in Fig. 2. In the present embodiment these channels ||0 are connected with the suction or inlet ports 85 of the end plates 60 by means of ports (Fig. 3) which are formed in the casing members 20 and 2| respectively and which are of substantially the same size and configuration as said ports 65. The channels ||0 may be connected with the supply of fluid at any desired point and in any desired manner and in the present -embodiment this' is eiected by means of the inlet opening ||2 which connects with said channels ||0 as indicated by the dotted lines in Fig. 3.

The uid circuit also comprises a pair of annular channels |5, one of'which is formed in each of the casing members 20 and 2| respectively as shown in Fig. 2. The channels I5 are, in the present instance, connected with the discharge or-high pressure ports 66 of the end plates 60 by means of ports ||6 (Fig. 3) which are formed in the casing members 20 and 2| respectively and which are of substantially the same size and configuration as the high pressure ports 66. Out. let for pressure fluid delivered into the channels I5 may be provided in any convenient place and manner and is here shown as comprising an outlet opening ||1 which connects with said channels ||5, as indicated by the dotted lines in Fig. 75..

52 of the rotor 50, as said lrotor 50 revolves, with the suction and with the high pressure portions of said fluid circuit. In the present instance this is accomplished by means of two pairsof arcuate ports 61 and 68 respectively, hereinafter termed balance ports, formed in the end plates 60. The balance ports 61 and 68 are here shown as positioned inwardly with respect to the ports 65 and 66 respectively (Fig. 7) and concentrically with respect to the inner ends of the slots 52 with which they are adapted to register as shown by dotted lines in Fig.- 3.

The 'balance ports 61 are adapted to be connected with the inlet or suction portion of the uid circuit and in` the present embodiment this is accomplished by means of drill holes |20 in the end plates 60 extending from the suction or inlet ports 65 to said balance ports 51. Similarly the balance ports 68 are adapted to be connectedwith the discharge or high pressure portion of the fluid' circuit and in the present embodiment sions 69 which serve to connect the inner ends of the slots A52 with the high pressure portion of the fluid circuit'while the vanes 55 are passing across part or all of thecorresponding pumping arc 9|..

This construction has several advantages; One;l

such advantage isv that the portions of the slots 52 between `their inner ends -and the inner ends` of the vanes 55 are connected with the fluid circuit` whenever any inward or outward movement of said vanes 55 is occurring, thus providing easy ingress and egress of the fluid. Another advantage is that the inner ends of the vanes 55 are supplied with fluid under the same pressure as that acting upon the outer endsof said vanes 55 whenever said vanes 55 are-moving across the flexible arms 92; the vanes 55 are thus maintained substantially in hydraulic balance so that the only pressure exerted by them upon the arms 92 is the pressure 'created by centrifugal force plus the'small amount of outward pressure brought about by the slight unbalanced effect due to the small area of the outer ends of said vanes 55 which is in contact with the interior surfaces of said arms '92. ,Still another advantage is that high pressure fluid is introduced behind the inner ends of the vanes 55 when said vanes begin to move across the pumping arcs 9! and before the fluid immediately ahead of 'said vanes 55 is connected with the high pressure portion of the fluid circuit; this tends to hold said vanes 55 firmly II1 is suitably connected with a reservoir or a uid device to be operated, as the case may be. t

Rotation of the rotor 50 sets up centrifugal force which is exerted upon the vanes 55, causing them to tend to move outwardly and 'holding t them` against the arcuate` surfaces 16 of the fixed abutments 15 and against the interior surfaces of the vane track elements 92.

For purposes of explanation, let us assume that the particular vane under consideration is -opposite the mid-point of the arcuate surface 16 of one of the fixed abutments 15. As shown in Figs. 1 and3, the vane 55 will then be in its exj treme inward position in its slot 52 where it will remain as long as its outer end isin contact with the arcuate surface 16. While still in this extreme inward position the vane 55 moves across the joint made by the tongue 11 of the fixed abutment and the forked end of the adjacent arm 92 and hence moves onto the interior surface of. said arm 92 where it begins its outward movement. This outward movement continues as the vane 55 isrnoved along on the arm 92 and occurs asrapidly as the contour of the inner surface of said arm 92 will permit, preferably reaching its extreme outward position at or about the point where said vane 55 enters the adjacent pumpin It will be'observed that outward movement of the vane 55 takes place while said vane is passing through a portion of the pump cavity which is connected through one o f ports 65 with the inlet or suction portion of the fluid circuit and it is intended that said inlet or suction portion of the fluid circuit and its connected portions of the pump cavity shall be kept completely illled with fluid; under ordinary circumstances this will be accomplished by the suction effect pro- 'duced by the action of the vanes 55 as the rotor 59 revolves, though gravity or other pressure means may be employed if desired. The leading and trailing faces of the vane 55 are therefore acted upon and exposed to fluid of uniform pressure as said vane 55 begins and as long as it continues its outward movement; the vane 55 is therefore hydraulically balanced and moves.

freely and easily in its slot 52, with no appreciable tendency to bind,

As the rotor 50 continues its rotation, the vane 55 passes from the inner end of the arm 92 onto .and through the adjacent pumping are 9 I. It will Pumping is accomplished as the vane moves across the pumping arc 9| and thus forces the fluid immediately ahead of said vane 55 into the high pressure or discharge portion of the pump cavity, whence it passes through one of ports 66 and through and out of the other high pressure or discharge portions of the iiuid cir- -cuit already described. It will be observed that there will be absolutely no radial movement of the vaneV 55 while passing across the pumping arc 9| when the movable abutment 60 is ,in such position oiV adjustment that said are 9| is concentric with the rotor 50; in other positions of adjustment of said movable abutment 80 there will, theoretically, be a very small radial movement of said vane 55 .as it passes across said arc 9| but in practice this movement is negligible. The approximate amount of such movement of the vane 55 can be observed from Fig. 4 in which the full line drawing of the movable abutment -80 employed in the present embodiment shows the are 9| in 'its concentric position 'while the 'inner and outer dotted lines show the relative positions of said arc 9| with respect to the axis of the rotor 50 when said movable abutment 80 is in its respectively extreme inward land outward positions of adjustment. By varying the number of vanes 55 and altering the proportions of the parts this radial movement may be held within almost any desired limits.

As the vane 55 leaves the pumping arc 9| it passes onto the inner surfaceof the inner end of the adjacent arm 92 'and into a portion of the pump cavity containing relatively high pressure liuid. 'I'hevane 55 now begins its inward movement which continues as it -travels along the inner surface of the arm 92 until said vane 55 is in its extreme inward position in its slot 52 as i't approaches the outer end of said arm 92, whence it passes across the joint formed by the forked end of said arm 92 and the tongue 11 of'the adjacent fixed abutment 15 and onto the arcuate surface 16 of said xed abutment 15. As in the case of the outward movement of the vane 55 and by means of similar fluid connections, the leading and trailing faces of said vane 55 are exposed to iiuid under uniform pressure, and hence hydrauflically balanced, whenever such inward movement is taking place.

It will be observed that the particular vane under considerationhas now travelled through a distance of 180 and the cycle already described will be repeated through the succeeding 180 of the vanes travel. Each vane 55 therefore undergoes two complete reciprocations and performs two pumping operations for each revolution of the rotor 50, so that the punp is of what is frequently termed the-- double acting type. It will also be observed that the pump comprises a pair of suction or low pressure areas and a pair of `discharge or high pressure areas, the respective members of which pairs are positioned diametrically opposite each other; land it will be further observed that the arrangement is such that for each portion of the rotor 59 exposed to iluid act- -ing upon it in one direction there isa corresponding and equal area of said rotor 50 exposed to fluid under same pressure but acting upon said rotor 50 in the opposite direction. The entire rotor 50 is therefore in hydraulic balance.

It .will still further be observed that the exible arms 92 are likewise in hydraulic balance and are subject to no outward force except the small' amount imposed by the vanes 55, as hereinbefore.

l The movable abutments 90 are, however, not in hydraulic balance since the rectangular portion 9|, i. e. the horizontal member, is directly behind' -the pumping arc or pumping space 9|. l There Vfore whenever any part of the pumpingarc is connected with the high pressure portion of the 75 :duid circuit, there will be a force acting to push r the second of this pair of the movable abutments outwardly. With the .tions of the circuit. When the lower of the pair of vanes opposite arc 9| moves down so as to connect with the valve port 66, however, all the fluid between this lower vane and the vane immediately atthe rear thereof will be put under high pressure. 'This will act upon the pumping arc 9| and attempt to push it outward, the area of p ping arc 9| thus actedupon decreasing as vanes(travels downward. I

The capacity or output ofthe pump per revolution is varied by changing the size of the pumping spaces by altering the positions of the movable abutments 89 with respect to the rotor 50 and; as hereinbefore explained, this is accomplished by rotation of the hand wheel |08. The capacity per revolution of the pump varies in proportion to the distance of the pumping arcs 9|, and hence of the movable abutments 80, from the periphery of the rotor 50 and as this distance may be varied in infinitely small increments, the capacity per revolution of the pump may likewise be varied from maximum to minimum. The length of the path of travel of the outer ends of the vanes along the vanetrackway peri revolution of the rotor 50 is increased or= decreased as the movable abutments 80 are movedoutwardly or inwardlyrespectively. The minimum capacity per revolution may be made zero by proper proportioning of the parts.

In assembling the'pump, an end plate 60 is rst put into place in thepump cavity 28 and adjacent the face 29 of thecasing member 20. The 'two central distance pieces 10 and the two movable abutments 80 are then assembled so thatthe tongues 11 extend into the slots 95 and so that the rectangular portions 8| are inV proper position between the opposing ends 1| of the central distance pieces 10; these parts thus assembled are then put into place in the pump cavity 28, care being used so that the flanges 94 are received within the channels 91 of the end plate 60 already pu't into place. The rotor-50 is then assembled with its vanes 55 in their corresponding slots 52 'and this assembly is.then' put into place. The driving shaft 40 is next inserted in the -bore of the rotor 50 and is keyed to said rotor by the I eys 45;.

the bearing member is then put into place, care again being used so that the flanges 94 are received into the channelsv 91. The bearing member 42 is then placed upon the rear 'end of the driving shaftdll and the cover member 2| is then put into place and securely fastened by means of the screws 24. The end of the bore 99 is then closed by means of the cover plate 34 and the bearing member 42 thus posi- `tioned against the shoulder 44 of the driving 1 shaft 40. The movableabutments 80 are then connected with the'adjusting mechanism in a manner which will be obvious.

The pump hereindescribed `possesses is then inserted in theA bore 21 and is located byclosing said bore l21", with its cover plate 32. The second end plate 60.

IIl'lllllel'OuS advantages.v vAmong these are that it is compact I and sturdy. It is simple in design and its component parts are likewise simple and adapted for quantity production, all of which results in low cost.- Its parts may readily'be held to close limits vso that said parts will be interchangeable and not require hand fitting. Substantially all move-v ment of the working parts occurs when such working parts are hydraulically balanced, thus reducing friction and wear Other advantages will be readily apparent to those skilled in the art. n

It will be understood that the rotor and vanes are balanced axially and -that hydraulic balance of the forces acting on `the rotor in a radial direction is obtained by arranging the inlet and outlet ports in pairs, one port of each pairbeing ar' ever, thatif desired, only a single fixed abutment and aY single movable abutment, i. e. a single Y pumping space may be employed.

In the Aforegoing description it has been assumed that the speed of the rotor is such that the resulting centrifugal force exerted'upon the varies will be sulcient to hold said varies 55 outwardly againstthe arcuate surfaces 'IB of the fixed abutments 15 and against the interior 'surfaces ofthe arms 92. In almost all instances this will be the case in ,ordinary practice but ifQit is desired to operate the pump at lower speeds appropriate means maybe 'introduced -to hold said varies 55 outwardly. A

While the device has` been described as a pump,

^` it will also function as a fluid motor if supplied with pressure fluid for its operation. The cycle of operation will, of coursebe reversed. When employed' as a motor it may be desired to locate the slots 5.2 in truly radial 'position with respect to the'rotor 50, particularly if the motor is intended to be operated in both directions of rotation. Likewise it may be desired to introducev means tending to hold the vanes 55 outwardly, particularly if the motor is intended to be operated at low rotative speeds.

It; is to be understood that the foregoingis l merely an exemplifying disclosure, and that l changes may be made in the apparatus without" departing from the applicants invention which is defined inthe appended claims.

I claim:

1. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable in wardly and outwardly in slots of said rotor, a track of variable circumferential length having a surface for guiding the ends of the vanes in their in--and-out movement, and means for si-y multaneously varying the circumferentiallength of the track and the capacity of the pump or motor, said track including fa flexible portion bendable to varying degrees-as the circumferential length of the track is varied to give the right curvature to produce a smooth guiding of the varies at any given capacity of the pump or motor.

2. In a rotary pump or motor of variable c'apacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a trackway for said vanes of variable length comprising two parts, and means forvarying the length of said trackway as the capacity of the pump or motor is variedhatleastone of said two parts of the trackway being movable with respect to the other part, and at least one of said 'parts including a flexible portion bendable to varying'degrees as the length of the trackway is varied, to cooperateA with said other part to maintaina smooth track surface for said vanes.

3. In a, rotary pump or motor of variable capacity, a casing, a rotor Within the casing. a plurality of vanes movable inwardly and outwardly of the rotor, a working chamber between' the rotor and a part of the casing, the working chamber having a fluid inlet and a fluid outlet, means for regulating the extent of the in-and-out movement of the vanes during a pumping cycle to vary the capacity of the working chamber of the pump or motor, said means including a track of variable circumferential length for the outer ends of the vanes, said track including a flexible portion bendable to varying degrees as the in-and-out movement is varied, and means for varying the circumferential length of the track and controlling the' bending of the flexible portion.

4. In a rotary pump or motor of variable capacity, a casing, a rotor within said casing, a plurality of vanes movable inwardly and outwardly of said rotor, a working chamber between the rotor and a part of the casing, said working chamber having a fluid inlet and a fluid outlet,

, means for regulating the extent of the inand'-out 'movement of the vanes during a pumping cycle 'to vary the capacity of the working chamber of the pump or motor, a track of variable circum- 1 celeration of the vanes'in their in-and-out movement is substantially uniform at any given capacity of the pump or motor.

5. In a rotary pump or motor of variable capacity, a rotor, a plurality of varies movable inwardly and outwardly of said rotor, and a trackway'for said vanes including a stationary track element and a track element movable to vary the capacity of said pump or motor, said movable track element having a substantially-rigid portion and a flexible portion having an end slidably connected to the stationary track element, means for guiding said end of said flexible portion to cause it to follow a predetermined path as said movable` track element is moved, and means for exerting force upon said flexible portion to simultaneously alter its configuration to control the acceleration and deceleration of said vanes in their in-and-out movement.-

6. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanesmovable inwardly and outwardly of said rotor, and means for varying the capacity of said pump or motor including a trackway for said vanes comprising a stationary element having a vane track surface of fixed curvature and an element movable with respect thereto to alter the capacity of the pump or motor and to vary the circumferential length df said trackway, said movable element having a ilexible portionengaging a vportion of said stationary element in all positions of said movable element. v

'7. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable invwardly'and outwardly of said rotor, a trackway for said vanes comprising a pair of cooperating elements having overlapping track surfaces, at least one of which includes a flexible part, and means for moving one of said elements with respect to the other to vary the capacity of the pump or'motor and to vary tliecircumferential l length of the trackway, said'iiexible part being varied to maintain the overlapping trackv surfaces of said cooperating members even.

8. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a track having a surface adapted to contact the exposed ends of said vanes, said track comprising a flexible f member and a rigidmember, means 'for bodily moving one of said members with respect to the vother to vary, the circumferential length of the i pacity, av rotor, a plurality of vanes movable inwardly and outwardly ofsaid rotor, a track for said vanes comprising a rigid element and a fiexible element, said elements having surfaces adapted to contact the vanes, means for moving one of said elements with respect to the other ,to vary the capacity of the pump or motor and to vary the circumferential length of said track, and means actuated simultaneously with said moving means vanes movable inwardly and outwardly of said for exerting force upon said flexible element to cause it to alter its shape.

10.y vIn a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a track for exerting guiding action on said vanes, said track including a rigid element and a flexible element connected to the rigid element, means for slidably moving one of said elements with. respect to the other to vary the capacity of the pump or motor, said movement causing' a variation in the circumferential length of the "track, and means for simultaneously bending a portion of said exible elementito maintain said guiding action on the vanes in all positions of relative movement of said elements.

11. Ina rotary pump of variable capacity, a casing, a rotor within said casing, a plurality of rotor, a working chamber between the rotor and a part of the casing, said chamber having a iiuid inlet` and a fluid outlet, a track of variable cir'- cumferential length coacting with the ends of the vanes in said chamber, said track including a member adjustable to vary the capacity of said chamber and a deformable part adjacent said inlet for limiting the outward position of said vanes during intake, means for varying the circumferential length of said track as the capacity of said working chamber is varied, means for'adjusting simultaneously said adjustable member and said deformable part, said means also acting to control the curvature of the inner face of said deformable part upon adjustment so that in all positions of adjustment lthe extent of outward movement of the vanes per unit of angular movement of the rotor is limited insuch'manner that the centrifugal force oi' the vanes alone is sufllcient to project them outwardly into-contact with said deformable part with sufllcient force to maintain them constantly' in contact therewith during intake.

1 2. In a rotary pump or motor 'of variable capacitya casing, a rotor within saidcasing, a

l element is adjusted.

bendable as the capacity of the pump .or motor is upon said flexible element in an inward radial -direction to increase the curvature thereof and shorten the circumferential length of the track and thereby decrease the capacity of the Working chamber, and mechanical means for exertingv force upon said -flexible element in an outward radial direction to decrease its curvature and increase the circumferential length of the track and thereby increase the capacity of the working chamber.

13. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a trackway for said vanes including a stationary element, an element movable to vary simultaneously the capacity of said pump or motor and the length of the trackway, and a flexible member fixed to one of said elements and having an extensible connection with the other of said elements.

14. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a trackway for said vanes including a stationary element, an element movable to vary the capacity of said pump or motor and to vary the circumferential length of said trackway, a flexible member fixed to one of said elements and having an extensible connection with the other of said elements to form a smooth and substantially co'ntinuous trackway from one of said elements to the other for .said vanes in all positions of said movable element, and means for altering the configuration of said flexible member to control the rate of movement of said vanes in said slots.

15. .In a rotary pump or'motor of variable capacity, a rotor, a plurality of vanes movable inwardly' and outwardly of said rotor, and a track for guiding the ends of said vanes comprising a stationary element of xed length and curvature, an element movable with respect to said stationary element to vary the capacity of the pump or motor and to Vary the circumferential length of the track, a third element whose vcurvature is variable'disposed intermediate said first and second-named track elements, vand means for controlling the curvature of said third element to correspond to the position to which said movable 16. In a vane type pump or motor of variable output having inlet and discharge chambers, a

rotor having a plurality of vane slots, vanes in said slots, a stationary abutment cooperating with said vanes to separate discharge and inlet chambers; a movable abutment cooperating with said vanes toseparate inlet and discharge chambers, means for altering the position'of saidmovable abutment to alter theV volume of fluid transferred from an inlet chamber to a discharge chamber, a track element connecting said abutments having a flexible portion and having an extensible connection with one of said abutments, and means for controlling the flexing of said flexible portion conformably to the adjustment of said movable abutment, I

17. .In a rotaryl pump or motor of variable ca-V pacity, .a rotor, a plurality of vanes movable inwardly `and outwardly of said rotor, a track having asurface`adapted to exert guiding action'on the exposed ends of said' vanes, said track intionary rigid element, and

rigid element, a staan intermediate ilexible element connecting said movable and stationary elements and having al1-extensible connection with one of said aforementioned elements, means for causing substantially rectilinear movement of said movable element to vary the -cacluding a bodily movable pacity of said pump or motor and to vary the a surface adapted to contact the exposed ends of said rigid elements. v

said vanes, said track including a stationary rigid element, a rigid element movable to vary Athe capacity of the pump or motor, and an .intermediate flexible, element, means Afor moving 'said movable rigid element, means for causing said movement to produce relative sliding movement between said flexible element ,and one of said rigid elements in a predetermined path to vary the circumferential length of said track and maintain the vane surfaces of said elements even with one another, and-means for exerting force upon said 4 flexible element to alter its curvature simultaneously with the movement of said'movable element.

19. In a rotary pump or motor of variable ca-l pacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, and a track having. a track surface for guiding the ends of said vanes comprising a stationary rigid element, a rigid element movable with respect thereto to adjust theY capacity of the pump or motor, and an intermediate flexible element adapted to 'connect said movable and stationary elements, said flexible element having an extensible connection with one of said rigid elements whereby movement of the movable element to vary the pump ormotor capacity alters the circumferential length of the track, means for supporting said intermediate element, and means for maintaining the ends of the track surface of said intermediate flexible element even with the track surfaces of 20. In a rotary pump of variable capacity, 'a casing, a rotor within said casing, av plurality of vanes movable inwardly and.- outwardly of said rotor, a working chamber between the rotor and .a part of the casing, said chamber having a fluid inlet and a fluid outlet, atrack of variable circumferential length coacting with the ends ofthe vanes in said chamber, said trackincluding a part adjustable to vary the capacity of said chamber anda deformable part adjacent said inlet, and a second deformable part adjacent said i outlet, which parts limit'the outward position of said vanes during intake and discharge, means for limiting the outward position of said vanes during intake, means fo'r varying the circumferential length of said track as the capacity of the working chamber is varied, means for adjusting simultaneously said adjustable member and said deformable parts, said means also acting to control the curvature of the inner face of said, deformable parts upon adjustment so that in all positions of adjustment the extent pf inwardland outward movementV of the vanes per unit of 'an-- gular movementof the rotor is limited in such manner that thel centrifugal force of the 4vanes alone is suilicient to maintain them constantly in pacltyr contact with said deformable parts during intake and4 discharge.

21. In a rotary pump-or motor of variable caa casing, a rotor within said casing, a plurality of vanes movable inwardly and outwardly in slots in said rotor,'a track of variable circumferential length having a surface for guiding the .vanes in their in-and-out movement in said slots,

said track comprising a stationary member, a member movable with respect to said stationary member to vary thecapacity of the pump or.

motor, and an intermediate member connecting the movable and stationary members and having a exible portion, and'means for moving saidvincluding a first abutment coacting with a portion of the peripheral surface of the rotary assembly, a` second abutment coacting with the vanes at another portion of said rotary assembly and adjustable radially with respect thereto,-one of said abutments having a flexible projection extending in an approximately circumferential direction to the other of said abutments and forming a traclrwayl element connecting said abutments to guide said vanes radially as they pass therebetween, means for maintaining the inner surface of theend of said projection even with the corresponding surface of its contiguous abutment as said movable abutment is adjusted .radially to vary the capacity of the pump or motor,'and an inlet and outlet for admitting and discharging fluid to and from said vanes.

23. In a variable capacity pump or motor, a rotary assembly including a rotor and substantially radially movable vanes, a casing therefor including aflrst abutment coacting with a portion of the peripheral surface of the rotary assembly, a second abutment coacting withthe vanes at' another portion'of said rotary assembly and adjustable radially with respect thereto, one of said abutments having a flexible projection extending-in an approximately circumferential direction to the other of said abutments and forming a trackway element connecting said abutments to guide said vanes4 radially as they pass therebetween, means for maintaining the track surface of the end of said projection in tangential relationship to the track surface of its contiguous abutment vas the lmovable abutment is adjusted radially to vary the pump capacity, and an inlet and outlet for admitting and discharging iluid to and from said vanes. 1

24. In a variable capacity pump or motor, a.

casing forming a pump chamber, a rotary assembly smaller than said chamber including a rotor and substantially radially movable vanes, two sta- -tionary members projecting into said vchamber from oppsite sides of the rotary assembly and dividing the chamberlinto twoV pumping sections, each of said 4stationary members having an arcuate face c'oacting with a portion of the peripheral surface of the rotary assembly, two radially movable members` each also having an arcuate face `enacting with the ends of thevanes of another'portlonof the rotary assembly, said movable members projecting into said chamber from opposite sides of said rotor intermediate said stationary members and dividing each of said pumping sections into an inlet portion, a pumping space and an outlet portion, said pumping space being substantially opposite the inner ends of .said radially movable members, flexible trackway elements extending between said radially movable members and said stationary members, one of said trackway elements being disposed in each of said inlet and outlet portions, means for adjusting the radial position of said movable members to vary' the capacity of said pump ormotor, and means for maintaining the end portions of said exible trackway elements even with the arcuate surfaces of said stationary and movable members in all positions of said movable members so as to cause said vanes to pass smoothly to and from said stationary members without abrupt changes in radial velocity.

25. In a :variable capacity pump or motor, a casing `forming a pump chamber. a rotary assem-4 bly smaller than said chamber including a rotor and substantially radially movable'vanes,` two able members each also having an arcuate face' coacting with the en ds of the vanes of another portion of the rotary assembly, said vmovable members projecting into said chamber from opposite sides of said rotor intermediate said sta-- tionary members and dividing each of said pumping sections into an inlet portion, vva. pumping space and an outlet portion, said pumping space ybeing substantially ,opposite the inner ends of said radially movable members, each of said .radially movable members having a-pair of ilexible resilient projections extending throughout one of said inlet and outlet portions respectively to a point adjacent said stationary' members, said projections forming trackway elements for guiding said vanes in their inward and outward radial movement as they pass between said stationary and movable members, means for adjusting the radial position of said movable members to vary the capacity of said pump or motor, and means Vfor bending the end portions of said exible regsillent trackway elements to maintain said portions'in proper relation to the arcuate surfaces of said xed abutments in all positions of said movable abutments to Acause said vanes to pass smoothly to and from said stationary members. without abrupt changes in radial velocity.

26. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a track having a surface adapted to contact the exposed ends of said vanes to act thereon to vcontrol the reciprocation thereoffsaid track including an element adjustable to vary the capacity of said pump or motor, and awcurved flexible element connected therewith, said exible element being free from force tending to change its curvature when in an intermediate position of adjustment, means for moving vsaid adjustable element. mechanical means for exerting force upon said ilexlble elesaid e "'e rient in a direction tending to de- 1 i crease its curvature when said adjustable element is movedin the opposite direction away from said force-free position.

27. In a rotary pump or motor of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a track having' a surface'adapted to contact the exposed ends of said vanes to act thereon to control the reciprocation thereof, said track including an element movable to vary the capacity of said pump or motor and a curved exible element connected therewith, said flexible element being free from vforce tending to change its'curvature when in an intermediate position of adjustment, means for moving said movable element with respect to A said exible element to ilex said flexible element and to vary the circumferential length of .said track, and. means simultaneously exerting force upon said iiexible element in a direction tending to vary its curvature to maintain said controlling action on the vanes in all positions to which said flexible element is adjusted from saidforcefree position.

28.- In a variable capacity pump or motor, a- -rotary assembly including a rotor and substantially radially movable vanes, a casing therefor including a ilrst abutment coacting with a portion of the peripheral surface of the rotary assembly, a second abutment coacting `with the vanes at another portion pf said rotary assembly and adjustable radially with respect thereto, one of said abutments having a flexible projection ex.. tending in an approximately circumferential direction to the other of said abutments and -forming a trackway element connecting said abutments to guide said vanes radially as they pass therebetween, and a substantially rigid radial member near the end of said exible projection, a.

curved arm concentric with the axis of the rotor extending from said rigid member, a guide therefor whereby when said movable abutment is adjusted radially the end of said iiexible projection is maintained even with its contiguous abutme '.t

of the peripheral surface of the rotary assembly,l

a movable abutment coacting with the vanes at.,A another portion of the rotary assembly and adjustable radially with respect thereto to vary the volume of the pumping space between adjacent vanes in contact with said' abutment, said movable abutment having a flexible projection extending in a substantiallycircumferentiafiirection to said ilxed ab utment, a rigid radial member near the ai: of 'said ilexible projection, a curved arm conc me with the axis of sain rotor attached to said. rigid member, a guidewayffn each of said walls for receiving the edge of said curved arm whereby .the inner surface of the end of said flexible projection is maintained even with the corresponding surface of said xed abutment and the configura--Hf tion of said flexible projection is inodiiied and coordinated with .the radial position of said movable abutment to cause said vanes to reciprocate without abrupt changes in the velocity of their radial movement, and an inlet and outlet for admitting and discharging fluid to and from said vanes.

30. In a fluid pump of variable output, a cas- 7s ing forming a pump chamber, a rotary assembly smaller than said chamber and including a rotor A and substantially radially movable vanes, a pumping section in said pump chamber terminating at each of its ends in a rigid member projecting into said chamber toward said rotor, a radially adjustable rigid member projecting into said chamber and dividing said pumping section into an inlet or low pressure area, a pumping vspace of variable volume and an outlet or. high pressure area, said pumping space being substantially opposite the inner end of said radially adjustable rigid member, an arcuate face on each of said rigid members equal in angular length to 'at least the distance between vanes and coacting with a portion of the periphery of the the movement of the venes along said flexible trackway elements so as to reduce1 the outward pressure o! the vanes against said flexible trackway elements to substantially that due to centrifugal. action alone.. means for adjusting the radial position of said radially adjustable rigid member and forgmaintaining said adjusted position in positively controlled relation to the radial position oi said rst named rigid members tov change the volume of the pumping space and to vary and control the output of the pump, and means for maintaining the end portions of said flexible trackway elements even with the arcuate surfaces ot said rigid members in all positions of 1- said adjustable rigid member to cause said vanes l to pass smoothly to and from said rigid members without abrupt changes in radial velocity.

31. In a vane type uid pump of variable output, a casing forming a pump chamber, a rotary assembly smaller than saidchamber and including a rotor having substantially radial vane slots ,y and vanes movable therein, a pumpingsection in said chamber terminating at each of its ends in a rigid member projecting into said chamber togrotarysssemblilexibletrsckwayeiementsextending betweenadjacent rigid members, said trackway elements being disposed one each in said high and low pressure areas respectively, means for equalizing the iluid pressures on the radially opposite ends of each vane throughout the movement-of the vanes along said exible trackway elements so as to reduce the outward pressure of the vanes against said flexible trackway elements to substantialy that due to centrifugal action alone, means for supplying uid from said high pressure area to the inner end of each vane as said vanes move through said working space to hold said vanes against the arcuate face of said radially adjustable rigid member, means for altering the position of said radially adjustable rigid member to alter the volume of iiuid transferred from one of said areas to another, 'and means for controlling the flexing of said exlble trackway elements to guide said vanes in their inward and outward movement without abrupt changes in the velocity of their radial movement.

32. In a rotary pump or motor of variable output, a rotor, a plurality of vanes movable inwardly and outwardly of said rotor, a track'for exerting guiding action on said venes comprising a rigid element and a exible element having an extensible connection therebetween including overlapping parts, means for moving one of said elements with respect to the other to vary the output of the `pump or motor and varying the length of said track, and means actuated simultaneously with said moving means for maintaining said overlapping parts even with one another and for flexing said exible element to produce a smooth guidingoi' the vanes at all outputs.

33. In a' rotary pump or motor of variable out- A put, a rotor, a plurality'of vanes movable inwardly and outwardly o'f said rotor, a track having a surface adaptedto contact the exposed ends lof said vanes to guide the same in their in-and-out movement, said'track including a stationary element of xed curvature also a rigid element of iixed curvature which is movable to vary the output of the pump or motor and an intermediate ilexible element, means for adjusting said movable element ,to vary said output, an extensible connection including overlapping parts between said flexible element and one of said elements of ilxed curvature, 'and means actuated simultaneously with the adjustment of said movable elementv for maintaining the overlapping parts of said extensible connection even with one another and for iiexing saidexible element to alter its curvature to produce a smooth guiding ot the vanes at all outputs.

. HUGO A. CENTERVALL. 

